Bisphosphonate use and the risk of subtrochanteric or femoral shaft fractures in older women

Bisphosphonates Use and Risk of Subtrochanteric and Diaphyseal Femur Fractures in Korea: Results from the National Claim Registry

Although Asian with bisphosphonate has been considered to have higher risk of subtrochanteric and diaphyseal femur (ST/DF) fractures, the occurrence of those fractures has been still unclear in Asia. The purpose of this study was to investigate the incidence rate of ST/DF fractures among bisphosphonate users from nationwide database in South Korea. Using national health insurance claim database, we only included the bisphosphonate users who took bisphosphonate for the first time in 2008 and evaluated the incidence rate of ST/DF fracture from 2008 to 2013. Non-user controls were matched to bisphosphonate users by propensity score matching with age and gender. Cox regression models were used to calculate hazard ratios of ST/DF fracture with and without adjustment for comorbidity. A total of 682 ST/DF fractures were observed among 348,311 bisphosphonate users. The incidence rate of ST/DF fracture among bisphosphonate users (37.75/100,000 person years, 95% CI 35.02-40.70) was higher compared with non-users (24.41/100,000 person years, 95% CI 22.31-26.71). The risk of ST/DF fracture was greater in bisphosphonate users compared with non-users (hazard ratio 1.541, 1.370-1.734; p < 0.001). The incidence rate of ST/DF fracture after bisphosphonate use could be determined in Korean patients, which can provide basal information for further studies on risk and benefit of continuing bisphosphonate.

Melatonin: Another avenue for treating osteoporosis?

Melatonin is a signal molecule that modulates the biological circadian rhythms of vertebrates. Melatonin deficiency is thought to be associated with several disorders, including insomnia, cancer, and cardiovascular and neurodegenerative diseases. Accumulating evidence has also indicated that melatonin may be involved in the homeostasis of bone metabolism. Age-related reductions in melatonin are considered to be critical factors in bone loss and osteoporosis with aging. Thus, serum melatonin levels might serve as a biomarker for the early detection and prevention of osteoporosis. Compared to conventional antiosteoporosis medicines, which primarily inhibit bone loss, melatonin both suppresses bone loss and promotes new bone formation. Mechanistically, by activating melatonin receptor 2 (MT2), melatonin upregulates the gene expression of alkaline phosphatase (ALP), bone morphogenetic protein 2 (BMP2), BMP6, osteocalcin, and osteoprotegerin to promote osteogenesis while inhibiting the receptor activator of NF-kB ligand (RANKL) pathway to suppress osteolysis. In view of the distinct actions of melatonin on bone metabolism, we hypothesize that melatonin may be a novel remedy for the prevention and clinical treatment of osteoporosis.

Prophylactic Fixation Can Be Cost-effective in Preventing a Contralateral Bisphosphonate-associated Femur Fracture

BACKGROUND

Bisphosphonates reduce the risk of fractures associated with osteoporosis but increase the risk of atypical subtrochanteric femur fractures. After unilateral atypical femur fracture, there is risk of contralateral fracture, but the indications for prophylactic fixation are controversial.

QUESTIONS/PURPOSES

The purpose of this study is to use Markov modeling to determine whether contralateral prophylactic femur fracture fixation is cost-effective after a bisphosphonate-associated atypical femur fracture and, if so, what patient-related factors may influence that determination.

METHODS

Markov modeling was used to determine the cost-effectiveness of contralateral prophylactic fixation after an initial atypical femur fracture. Simulated patients aged 60 to 90 years were included and separated into standard and high fracture risk cohorts. Patients with standard fracture risk were defined as those presenting with one atypical femur fracture but without symptoms or findings in the contralateral femur, whereas patients with high fracture risk were typified as those with more than one risk factor, including Asian ethnicity, prodromal pain, femoral geometry changes, or radiographic findings in the contralateral femur. Outcome probabilities and utilities were derived from studies matching to patient characteristics, and fragility fracture literature was used when atypical femur fracture data were not available. Associated costs were largely derived from Medicare 2015 reimbursement rates. Sensitivity analysis was performed on all model parameters within defined ranges.

RESULTS

Prophylactic fixation for a 70-year-old patient with standard risk for fracture costs USD 131,300/quality-adjusted life-year (QALY) and for high-risk patients costs USD 22,400/QALY. Sensitivity analysis revealed that prophylaxis for high-risk patients is cost-effective at USD 100,000/QALY when the cost of prophylaxis was less than USD 29,400, the probability of prophylaxis complications was less than 21%, or if the patient was younger than 89 years old. The parameters to which the model was most sensitive were the cost of prophylaxis, patient age, and probability of prophylaxis-related complications.

CONCLUSIONS

Prophylactic fixation of the contralateral side after unilateral atypical femur fracture is not cost-effective for standard-risk patients but is cost-effective among high-risk patients between 60 and 89 years of age with a high risk for an atypical femur fracture defined by patients with more than one risk factor such as Asian ethnicity, prodromal pain, varus proximal femur geometry, femoral bowing, or radiographic changes such as periosteal beaking and a transverse radiolucent line. However, our findings are based on several key assumptions for modeling such as the probability of fractures and complications, the costs associated for each health state, and the risks of surgical treatment. Future research should prospectively evaluate the degree of risk contributed by known radiographic and demographic parameters to guide management of the contralateral femur after a patient presents with an atypical femur fracture.

LEVEL OF EVIDENCE

Level III, economic and decision analyses.

Incidence of Lower-Extremity Fractures in US Nursing Homes

BACKGROUND/OBJECTIVES

Limited studies suggest lower-extremity (LE) fractures are morbid events for nursing home (NH) residents. Our objective was to conduct a nationwide study comparing the incidence and resident characteristics associated with hip (proximal femur) vs nonhip LE (femoral shaft and tibia-fibula) fractures in the NH.

DESIGN

Retrospective cohort study.

SETTING

US NHs.

PARTICIPANTS

We included all long-stay residents, aged 65 years or older, enrolled in Medicare from January 1, 2008, to December 31, 2009 (N = 1 257 279). Residents were followed from long-stay qualification until the first event of LE fracture, death, or end of follow-up (2 years).

MEASUREMENTS

Fractures were classified using Medicare diagnostic and procedural codes. Function, cognition, and medical status were obtained from the Minimum Data Set prior to long-stay qualification. Incidence rates (IRs) were calculated as the total number of fractures divided by person-years.

RESULTS

During 42 800 person-years of follow-up, 52 177 residents had an LE fracture (43 695 hip, 6001 femoral shaft, 2481 tibia-fibula). The unadjusted IRs of LE fractures were 1.32/1000 person-years (95% confidence interval [CI] = 1.27-1.38) for tibia-fibula, 3.20/1000 person-years (95% CI = 3.12-3.29) for femoral shaft, and 23.32/1000 person-years (95% CI = 23.11-23.54) for hip. As compared with hip fracture residents, non-hip LE fracture residents were more likely to be immobile (58.1% vs 18.4%), to be dependent in all activities of daily living (31.6% vs 10.8%), to be transferred mechanically (20.5% vs 4.4%), to be overweight (mean body mass index = 26.6 vs 24.0 kg/m² ), and to have diabetes (34.8% vs 25.7%).

CONCLUSIONS

Our findings that non-hip LE fractures often occur in severely functionally impaired residents suggest these fractures may have a different mechanism of injury than hip fractures. The resident differences in our study highlight the need for distinct prevention strategies for hip and non-hip LE fractures.

Mechanisms Underlying Normal Fracture Healing and Risk Factors for Delayed Healing

PURPOSE OF REVIEW

Substantial advances have been made in understanding the biological basis of fracture healing. Yet, it is unclear whether the presence of osteoporosis or prior or current osteoporosis therapy influences the healing process or is associated with impaired healing. This review discusses the normal process of fracture healing and the role of osteoporosis and patient-specific factors in relation to fracture repair.

RECENT FINDINGS

The definitive association of osteoporosis to impaired fracture healing remains inconclusive because of limited evidence addressing this point. eStudies testing anabolic agents in preclinical models of ovariectomized animals with induced fractures have produced mostly positive findings showing enhanced fracture repair. Prospective human clinical trials, although few in number and limited in design and to testing only one anabolic agent, have similarly yielded modestly favorable results. Interest is high for exploring currently available osteoporosis therapies for efficacy in fracture repair. Definitive data supporting their efficacy are essential in achieving approval for this indication.

Cortical Bone Material Strength Index and Bone Microarchitecture in Postmenopausal Women With Atypical Femoral Fractures

Atypical femoral fractures are rare fractures that occur in the subtrochanteric or diaphyseal region of the femur with minimal or no trauma. Though the association of atypical femoral fractures (AFFs) and bisphosphonate (BP) use is a growing concern in the management of osteoporosis, currently there is little knowledge about which patients may be at risk for an atypical femoral fracture. Given that these fractures initiate in the femoral cortex, we aimed to determine whether cortical bone tissue properties (bone material strength index; BMSi), as measured by in vivo impact microindentation, are altered in atypical fracture patients. We also aimed to identify factors associated with the BMSi measurements. We enrolled postmenopausal women with recent AFFs (n = 15) or hip fractures (Hip Fxs; n = 20), long-term (>5 years) BP users (n = 30), and treatment naïve controls (n = 88). We measured total hip and femoral neck BMD by DXA, cortical bone microstructure at the distal tibia by HR-pQCT, and BMSi at the midtibia by impact microindentation. BMSi values were similar in all groups, with no effects of long-term BP use or lower values in patients with AFFs or Hip Fxs, even after multivariable adjustment. BMSi measurements were independent of age, femoral BMD, duration of BP treatment, vitamin D level, and cortical bone microstructure, including cortical porosity and cortical tissue mineral density. In conclusion, impact microindentation values are not negatively affected by long-term BP use and do not appear to discriminate individuals who suffer AFFs. Thus, our results do not support clinical use of impact microindentation to identify those at risk for AFFs. This remains to be verified in larger studies. © 2018 American Society for Bone and Mineral Research.

Can Melatonin Improve the Osteopenia of Perimenopausal and Postmenopausal Women? A Meta-Analysis

OBJECTIVE

To assess the effectiveness and safety of melatonin for perimenopausal and postmenopausal women with osteopenia.

METHODS

In this meta-analysis, data from randomized controlled trials were obtained to assess the effects of melatonin versus placebo or western medicine in perimenopausal and postmenopausal women with osteopenia. The study's registration number is CRD42018086238. The primary outcomes included bone mineral density (BMD) and T-score.

RESULT

From 551 articles retrieved, three trials involving 121 patients were included. Due to the high-to-substantial heterogeneity (BMD: I²=96.9%, P=0.000; T-score: I²=74.9%, and P=0.019), the statistical analysis of BMD and T-score was abandoned. A systematic review was undergone for the two outcomes. Compared with the control group, melatonin may increase osteocalcin (WMD 4.97; 95% CI 3.14, 6.79; P < 0.00001).

CONCLUSION

Based on current evidence, melatonin might be used as a safe nutritional supplement to improve bone density in perimenopausal and postmenopausal women, but its efficacy needs to be further affirmed.

Tart Cherry Prevents Bone Loss through Inhibition of RANKL in TNF-Overexpressing Mice

Current drugs for the treatment of rheumatoid arthritis-associated bone loss come with concerns about their continued use. Thus, it is necessary to identify natural products with similar effects, but with fewer or no side effects. We determined whether tart cherry (TC) could be used as a supplement to prevent inflammation-mediated bone loss in tumor necrosis factor (TNF)-overexpressing transgenic (TG) mice. TG mice were assigned to a 0%, 5%, or 10% TC diet, with a group receiving infliximab as a positive control. Age-matched wild-type (WT) littermates fed a 0% TC diet were used as a normal control. Mice were monitored by measurement of body weight. Bone health was evaluated via serum biomarkers, microcomputed tomography (µCT), molecular assessments, and mechanical testing. TC prevented TNF-mediated weight loss, while it did not suppress elevated levels of interleukin (IL)-1β and IL-6. TC also protected bone structure from inflammation-induced bone loss with a reduced ratio of receptor activator of nuclear factor kappa-B ligand (RANKL)/osteoprotegerin (OPG) to a degree comparable to infliximab. Furthermore, unlike with infliximab, TC exhibited a moderate improvement in TNF-mediated decline in bone stiffness. Thus, TC could be used as a prophylactic regimen against future fragility fractures in the context of highly chronic inflammation.

Incidence, risk factors, and fracture healing of atypical femoral fractures: a multicenter case-control study

The incidence of atypical femoral fractures (AFFs) was 2.95% among 6644 hip and femoral fractures. Independent risk factors included the use of bisphosphonates (BPs), osteopenia or osteoporosis, rheumatoid arthritis, increased femoral curvatures, and thicker femoral cortices. Patients with AFFs and BP treatment were more likely to have problematic healing than those with typical femoral fractures (TFFs) and no BP treatment.

INTRODUCTION

To determine the incidence and risk factors of atypical femoral fractures (AFFs), we performed a multicenter case-control study. We also investigated the effects of bisphosphonates (BPs) on AFF healing.

METHODS

We retrospectively reviewed the medical records and radiographs of 6644 hip and femoral fractures of patients from eight tertiary referral hospitals. All the radiographs were reviewed to distinguish AFFs from TFFs. Univariate and multivariate logistic regression analyses were performed to identify risk factors, and interaction analyses were used to investigate the effects of BPs on fracture healing.

RESULTS

The incidence of AFFs among 6644 hip and femoral fractures was 2.95% (90 subtrochanter and 106 femoral shaft fractures). All patients were females with a mean age of 72 years, and 75.5% were exposed to BPs for an average duration of 5.2 years (range, 1-17 years). The use of BPs was significantly associated with AFFs (p < 0.001, odds ratio = 25.65; 95% confidence interval = 10.74-61.28). Other independent risk factors for AFFs included osteopenia or osteoporosis, rheumatoid arthritis, increased anterior and lateral femoral curvatures, and thicker lateral femoral cortex at the shaft level. Interaction analyses showed that patients with AFFs using BPs had a significantly higher risk of problematic fracture healing than those with TFFs and no BP treatment.

CONCLUSIONS

The incidence of AFFs among 6644 hip and femoral fractures was 2.95%. Osteopenia or osteoporosis, use of BPs, rheumatoid arthritis, increased anterior and lateral femoral curvatures, and thicker lateral femoral cortex were independent risk factors for the development of AFFs. Patients with AFFs and BP treatment were more likely to have problematic fracture healing than those with TFFs and no BP treatment.

Does zoledronate therapy make mandibular bone susceptible to fracture? A radiographical and biomechanical study in rats

INTRODUCTION

The aim of this study was to evaluate the effect of zoledronate therapy on susceptibility of mandibular bone to fracture in rats.

METHODS

Fifty rats were randomly allocated to two groups of 25 animals. The rats in group Z received monthly intravenous infusion of 0.06 mg/kg zoledronate for 6 months. The rats in the group C were injected with an equal volume of saline in the same manner. A month after the last zoledronate/saline administration, all 50 rats were euthanized. Using a cone beam computed tomography, the cortical thickness of inferior border of mandible and the mandibular bone mineral density were calculated, and using a three-point bending test, the peak load failure and the ultimate stress of mandibular bone were determined.

RESULTS

The mean mandibular inferior cortical bone thickness and the mean bone mineral density were significantly larger in zoledronate-treated rats (0.30 ± 0.02 mm and 1045.00 ± 185.79, respectively) compared to control rats (0.21 ± 0.01 mm and 878.66 ± 166.53, respectively). The peak load and the ultimate stress were lower in the zoledronate-treated hemimandibles (84.61 ± 33.62 N and 1.76 ± 0.72 MPa, respectively) compared to the control hemimandibles (98.36 ± 16.5 9 N and 2.03 ± 0.44 MPa, respectively).

CONCLUSION

Zoledronate therapy reduced the mechanical strength of the mandibles, implying an increased risk of mandibular fracture in rats.

The Beneficial Effect of Proanthocyanidins and Icariin on Biochemical Markers of Bone Turnover in Rats

Nutrition is an important factor that influences bone metabolism, the endocrine and/or paracrine system, and bone-active mineral elements homeostasis. We studied antiosteoporotic effects of grape seed proanthocyanidins extract, icariin or alendronate (ALN) in retinoic acid-induced (13cRA) bone loss in rats. Proanthocyanidins and icariin have beneficial effects on bone health; they have improved the bone weight reduction, the length and the diameter of the bone, calcium, and phosphorus content in bone ash, bone mineral density (BMD), the biochemical markers of bone turnover and uterus atrophy induced by 13cRA. All results suggest that proanthocyanidins and icariin reverse osteoporosis in 13cRA rats by stimulating bone formation or regulating bone resorption by their antioxidative and estrogenic-like activity without toxic side-effects observed in ALN treatment.

Effects of bisphosphonates in preventing periprosthetic bone loss following total hip arthroplasty: a systematic review and meta-analysis

BACKGROUND

Periprosthetic bone loss following total hip arthroplasty (THA) was a well-known phenomenon. This systematic review was to assess the effectiveness of bisphosphonates (BPs) for decreasing periprosthetic bone resorption.

METHODS

The MEDLINE, EMBASE, and Cochrane Library databases were searched up to March 2018. Randomized controlled trials compared the effects between administrating BPs and placebo or no medication were eligible; the target participants were patients who underwent THA. Mean differences (MD) and 95% confidence interval (95% CI) were calculated by using the random-effects models. Statistical analyses were performed by RevMan 5.3 software.

RESULTS

Fourteen trials involving 620 patients underwent THA were retrieved. BPs significantly prevented the loss of periprosthetic bone mineral density at 1 year (MD, 0.06 [95% CI, 0.03 to 0.08], p < 0.001), between 2 and 4 years (MD, 0.04 [95% CI, 0.01 to 0.07], p = 0.02), and more than 5 years after THA (MD, 0.08 [95% CI, 0.06 to 0.11], p < 0.001). Both serum bone alkaline phosphatase (MD, - 7.28 [95% CI, - 9.81 to - 4.75], p < 0.001) and urinary N-telopeptide of type I collagen (MD, - 24.37 [95% CI, - 36.37 to - 12.37], p < 0.001) in BP group were significantly lower. Subgroup analyses showed that the third-generation BPs were more effective in decreasing periprosthetic bone loss than the first and second generation within 1 year after THA (p = 0.001).

CONCLUSION

BPs were beneficial to decreasing periprosthetic bone loss. The third-generation BPs showed significantly efficacy for patients in short-term observation.

Prevalence and Risk Factors of Atypical Femoral Fracture Bone Scintigraphic Feature in Patients Experiencing Bisphosphonate-Related Osteonecrosis of the Jaw

Purpose

Bisphosphonate (BP) is the first-line therapy for the management of osteoporosis. BP-related osteonecrosis of the jaw (BRONJ) and atypical femoral fracture (AFF) are increasingly common comorbidities in patients with osteoporosis under long-term BP treatment. The aim of this study was to evaluate the incidence and risk factors for AFF features on bone scintigraphy in patients with BRONJ.

Methods

Among total of 373 BRONJ patients treated between September 2005 and July 2014, 237 (220 women, 17 men; median age 73 years) who underwent three-phase bone scintigraphy were enrolled for this retrospective study. AFF features on bone scintigraphy and the related clinical factors were assessed.

Results

Among 237 patients with BRONJ, 11 (4.6%) showed AFF features on bone scintigraphy. BP medication duration (p = 0.049) correlated significantly with AFF features on bone scintigraphy in patients with BRONJ. BP intake duration of 34 months was the cutoff value for predicting the presence of AFF features on bone scintigraphy. Among the patients with BRONJ, all those with AFF features on bone scintigraphy were female patients with osteoporosis who were on oral BP medication; however, these factors were not significantly different along with AFF features on bone scintigraphy.

Conclusion

The incidence of AFF features on bone scintigraphy was relatively high in patients with BRONJ. A careful observation of patients presenting with the AFF features on bone scintigraphy may be needed, particularly for female BRONJ patients with osteoporosis who have been on BP medication for over 34 months.

Bone health in type 1 diabetes

PURPOSE OF REVIEW

This article reviews recent publications on the effect of type 1 diabetes (T1D) on fracture risk, bone mineral density (BMD), bone structure, and bone tissue quality. Possible fracture prevention strategies for patients with T1D have also been reviewed.

RECENT FINDINGS

T1D is associated with substantially elevated fracture risk and modestly low BMD at the femoral neck. However, BMD alone does not explain higher observed fracture risk in T1D. T1D also affects bone macro- and microstructure, characterized by thinner cortices and trabecular bone changes such as thinner and more widely spaced trabeculae. Structural bone deficit is pronounced in the presence of microvascular complications. Tissue-level changes, such as accumulation of advanced glycation endproducts, detrimental alterations of the mineral phase because of low bone turnover, and occlusion of vascular channels in bone by mineralized tissue, are implicated in pathophysiology of bone fragility in T1D. There are no guidelines on screening and prevention of osteoporotic fractures in T1D.

SUMMARY

More studies are needed to understand the influence of T1D on structural bone quality and tissue material properties. There is a need for a prospective study to evaluate better screening strategies for diagnosis and treatment of osteoporosis in T1D.

The Challenges and Opportunities of Pharmacoepidemiology in Bone Diseases

Pharmacoepidemiology is used extensively in osteoporosis research and involves the study of the use and effects of drugs in large numbers of people. Randomized controlled trials are considered the gold standard in assessing treatment efficacy and safety. However, their results can have limited external validity when applied to day-to-day patients. Pharmacoepidemiological studies aim to assess the effect/s of treatments in actual practice conditions, but they are limited by the quality, completeness, and inherent bias due to confounding. Sources of information include prospectively collected (primary) as well as readily available routinely collected (secondary) (eg, electronic medical records, administrative/claims databases) data. Although the former enable the collection of ad hoc measurements, the latter provide a unique opportunity for the study of large representative populations and for the assessment of rare events at relatively low cost. Observational cohort and case-control studies, the most commonly implemented study designs in pharmacoepidemiology, each have their strengths and limitations. However, the choice of the study design depends on the research question that needs to be answered. Despite the many advantages of observational studies, they also have limitations. First, missing data is a common issue in routine data, frequently dealt with using multiple imputation. Second, confounding by indication arises because of the lack of randomization; multivariable regression and more specific techniques such as propensity scores (adjustment, matching, stratification, trimming, or weighting) are used to minimize such biases. In addition, immortal time bias (time period during which a subject is artefactually event-free by study design) and time-varying confounding (patient characteristics changing over time) are other types of biases usually accounted for using time-dependent modeling. Finally, residual "uncontrolled" confounding is difficult to assess, and hence to account for it, sensitivity analyses and specific methods (eg, instrumental variables) should be considered.

Incidence of Mutations in the ALPL, GGPS1, and CYP1A1 Genes in Patients With Atypical Femoral Fractures

Atypical femoral fractures (AFFs) are uncommon and often related to prolonged bisphosphonate (BP) treatment. Isolated cases have been linked to mutations of tissue nonspecific alkaline phosphatase (ALPL). Moreover, mutations in the geranylgeranyl pyrophosphate synthase (GGPPS) gene, which can be inhibited by BPs, and in the enzyme of the cytochrome P450 superfamily (CYP1A1), related to the metabolism of several drugs, have also been associated with AFF development. Our aim was to analyze the incidence of ALPL, GGPS1, and CYP1A1 gene mutations in patients with AFFs and their clinical characteristics. Seventeen women with AAFs were included. All patients underwent Sanger sequencing of the ALPL, GGPS1, and CYP1A1 genes, analyzing the presence of mutations and polymorphisms in these genes. The clinical characteristics of the patients, previous treatments, ALP substrates (vitamin B6 and phosphoethanolamine), bone turnover markers, and bone mass were also analyzed. Three of 17 patients (17.6%) presented heterozygous mutations in the ALPL (p.Gly288Ala) or CYP1A1 (p.Arg136His, p.Val409Ile) genes. Only the patient with the ALPL mutation presented increased ALP substrates. Patients with CYP1A1 variants had glucocorticoid-induced osteoporosis. All patients were previously treated with BPs during 85.5 ± 38 months, and nearly 50% were also treated with glucocorticoids. The AFF was bilateral in 35% of cases. In conclusion, ALPL and CYP1A1 mutations may be related to the development of AFF in patients treated with BPs. The evaluation of ALP substrates in patients with low ALPL levels allows the identification of patients with hypophosphatasia. The role of CYP1A1 mutations in AFF needs further study. © 2018 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

Osteoporosis: Current Concepts

Osteoporosis is a worldwide disease characterized by reduction of bone mass and alteration of bone architecture resulting in increased bone fragility and increased fracture risk. Causes of osteoporosis include increasing age, female sex, postmenopausal status, hypogonadism or premature ovarian failure, low body mass index, ethnic background, rheumatoid arthritis, low bone mineral density (BMD), vitamin D deficiency, low calcium intake, hyperkyphosis, current smoking, alcohol abuse, immobilization, and long-term use of certain medications. The diagnosis of osteoporosis is established by measurement of BMD of the hip and spine using dual energy X-ray absorptiometry. According to the World Health Organization criteria, osteoporosis is defined as a BMD that lies 2.5 standard deviation or more below the average value for young healthy women. Bone turnover biomarker detection may be useful in monitoring osteoporosis treatment and assessing fracture risk but not for diagnosis of osteoporosis. Management of osteoporosis consists of nonpharmacological interventions, which are recommended for all subjects, and pharmacological therapy in all postmenopausal women who have had an osteoporotic fracture or have BMD values consistent with osteoporosis.

Critical differences between subtrochanteric and diaphyseal atypical femoral fractures: analyses of 51 cases at a single institution in Korean population

There still remains controversy on the pathomechanism of atypical femoral fracture (AFF). The angle of lateral bowing and bone mineral density showed significant differences between subtrochanteric and diaphyseal atypical fracture groups. In addition to the use of bisphosphonate, mechanical factors might play important roles in the occurrence of AFFs.

INTRODUCTION

Although AFF could be divided into subtrochanteric and diaphyseal fracture according to the location of fractures, there is a lack of evidence regarding differences between two fractures and etiology of the occurrence. The aim of study is to determine differences between atypical subtrochanteric and diaphyseal fracture in Korean population.

METHODS

Between February 2010 and March 2015, 51 AFFs in 40 patients were included in this study. Their medical records were retrospectively reviewed. The AFF patients satisfied all the diagnostic criteria of the 2014 revised edition of the ASMBR. To analyze the differences according to the location of fracture, the AFFs were divided into subtrochanteric (n = 16) and diaphyseal (n = 35) fracture groups. The following factors were compared between two groups: patients' demographics, underlying diseases, laboratory findings (serum-25(OH) VitD3, osteocalcin, c-telopeptide, ALP, Ca, and P), bone mineral density (BMD), duration of bisphosphonate (BP) usage, and lateral bowing of the femur at time of the fracture.

RESULTS

All AFFs happened in female patients (mean age, 73.8 years) who have received bisphosphonate treatments except three patients. The mean duration of bisphosphonate usage was 95.3 months. Between the two groups, demographic data (age, height, weight, and BMI), underlying diseases, laboratory findings, hip BMD, and duration of BP treatment were comparable to each other (p > 0.05). However, the subtrochanteric fracture group showed higher FNSBA (femoral neck shaft bowing angle, p < 0.001) and spine BMD (p = 0.014) compared to the diaphyseal fracture group.

CONCLUSIONS

Angle of lateral bowing (FNSBA) and spine BMD showed significant differences between subtrochanteric and diaphyseal atypical fracture groups. According to our results, femoral bowing and spine BMD may play important roles in the AFF locations.

Implications of guidelines for osteoporosis and its treatment

The development of clinical guidelines is now a more uniform process, with formalised methods to ensure that recommendations are based on current best available evidence from randomised controlled trials and systematic reviews. Over the past 20 years we have seen a growth in guidelines including those relating to osteoporosis, with recommendations varying between and within countries. Some guidelines are concerned with case finding and primary or secondary prevention, such as those produced by the National Institute for Health and Care Excellence (NICE CG146, TA-160, -161, -464), while others focus on specific conditions or risk factors associated with osteoporosis, such as the menopause, coeliac disease and eating disorder. Clinicians can be confused as to which to follow in any particular clinical scenario. International guidelines, such as those from North America (NOF, CAROC, AACE) and Scotland (SIGN 142), differ from those of England, Wales and Northern Ireland, with recent recommendations from NICE (TA464) shifting the focus of treatment from those at greatest fracture risk to an apparent blanket approach, based on cost-effectiveness, rather than clinical effectiveness.Osteoporosis treatment should be targeted at those who can benefit most, outweighing the potential for harm. If the low health economic threshold of NICE TA464 were adopted as a clinical threshold, the most important group-older people at greatest risk of fracture, would not be prioritised. We risk overwhelming clinical services, while causing harm to some at low fracture risk from adverse effects of treatment, yet failing to treat the older population at highest fracture risk.

Atypical fractures: An issue of concern or a myth?

Atypical Femoral Fractures (AFF) represent fractures located between the lesser trochanter and the supracondylar flare of a femur. An increasing pool of evidence supports their association with the prolonged use of bisphosphonates, even though a direct correlation is yet to be proved. The purpose of this review is to encapsulate the current evidence associating bisphosphonate use and the development of AFFs, the clinical features related to their presentation, as well as to report the armamentarium of strategies available in the prevention and treatment of AFFs. Based on these evidence, we propose a management algorithm for AFFs, that can serve as a guide for patients presenting with this condition.

Teriparatide for treatment of patients with bisphosphonate-associated atypical fracture of the femur

The Fracture Improvement with Teriparatide (Fix-IT) study randomized 13 women with an atypical femur fracture to immediate vs delayed teriparatide therapy; all were followed for 12 months. Results suggested a trend for superior healing and lesser bone mineral density declines in the immediate vs delayed group with no differences in adverse events.

PURPOSE

Little clinical data are available on the use of teriparatide for the treatment of bisphosphonate-associated atypical femur fractures (AFF). The goal of the Fix-IT study was to determine if immediate therapy with teriparatide was superior for fracture healing after an AFF compared to a 6-month delay in teriparatide therapy.

METHODS

This randomized pilot clinical trial included 13 women with an AFF who were randomized to immediate teriparatide vs a delay of 6 months. All were followed for 12 months on teriparatide. The primary outcomes included individual and composite measures of radiologic bone healing (scored 1 point [no healing] to 4 points [complete healing]) at 6 and 12 months. Secondary outcomes included bone mineral density of the unfractured contralateral hip, spine, 1/3 distal radius, and adverse events.

RESULTS

We found there was a trend for superior healing with the composite score (12.6 vs 11.2 at 6 months and 15.4 vs 13.2 at 12 months), and lesser bone mineral density declines at the 1/3 distal radius (12-month change - 1.9 vs - 6.1%) in the immediate vs the delayed group. There were no differences in adverse events. There was one implant failure in the delayed group.

CONCLUSIONS

There is a preliminary signal for greater improvements with immediate teriparatide therapy vs delayed therapy. However, because an AFF is a rare event, and only a small number of patients were included, the results must be interpreted with caution.

Incretin-based therapy for the treatment of bone fragility in diabetes mellitus

Bone fractures are common comorbidities of type 2 diabetes mellitus (T2DM). Bone fracture incidence seems to develop due to increased risk of falls, poor bone quality and/or anti-diabetic medications. Previously, a relation between gut hormones and bone has been suspected. Most recent evidences suggest indeed that two gut hormones, namely glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), may control bone remodeling and quality. The GIP receptor is expressed in bone cells and knockout of either GIP or its receptor induces severe bone quality alterations. Similar alterations are also encountered in GLP-1 receptor knock-out animals associated with abnormal osteoclast resorption. Some GLP-1 receptor agonist (GLP-1RA) have been approved for the treatment of type 2 diabetes mellitus and although clinical trials may not have been designed to investigate bone fracture, first results suggest that GLP-1RA may not exacerbate abnormal bone quality observed in T2DM. The recent design of double and triple gut hormone agonists may also represent a suitable alternative for restoring compromised bone quality observed in T2DM. However, although most of these new molecules demonstrated weight loss action, little is known on their bone safety. The present review summarizes the most recent findings on peptide-based incretin therapy and bone physiology.

Incidence Rate of Atypical Femoral Fracture after Bisphosphonates Treatment in Korea

BACKGROUND

Atypical femoral fracture (AFF) has been high-lightened, because it was associated with the long-term use of bisphosphonate. Comparing western countries, the incidence rate of AFF was unclear in East Asian patients. Our purposes were to estimate the incidence rate of radiologically defined AFF in Korea, and to determine the association between occurrence of AFF and long-term use of bisphosphonate.

METHODS

We conducted a hospital-based, retrospective cohort study in patients aged ≥ 45 years, who took bisphosphonate. The occurrence of AFF was estimated by using incidence rate, and the age-adjusted incidence rate to U.S. 2010 Census data. The association between occurrence of AFF and the duration of bisphosphonate use was examined. The cumulative probability of AFF was plotted per each duration of bisphosphonate use.

RESULTS

Among 10,338 individuals who took bisphosphonate, 13 patients with AFF following use of bisphosphonate were identified. The incidence rate was 85.9/100,000 person-years (95% confidence interval [CI], 50.2-146.9), and age-adjusted incidence rate was 72.7/100,000 person-years (95% CI, 29.1-175.8). In Poisson regression analysis, higher body mass index (BMI) was associated with an increased risk of AFF (relative risk, 1.2; 95% CI, 1.004-1.359). The cumulative probability of AFF increased abruptly when the duration of bisphosphonate use was 4 years or more.

CONCLUSION

Among Korean patients, the incidence rate of AFF was on a par with those of western countries, and this can provide basic information to conduct further studies by evaluating risk and benefit of continuing bisphosphonate.

Practice patterns in the care of acute Achilles tendon ruptures : is there an association with level I evidence?

AIMS

To determine whether the findings from a landmark Canadian trial assessing the optimal management of acute rupture of the Achilles tendon influenced the practice patterns of orthopaedic surgeons in Ontario, Canada.

MATERIALS AND METHODS

Health administrative databases were used to identify Ontario residents ≥ 18 years of age with an Achilles tendon rupture from April 2002 to March 2014. The rate of surgical repair (per 100 cases) was calculated for each calendar quarter. A time-series analysis was used to determine whether changes in the rate were chronologically related to the dissemination of results from a landmark trial published in February 2009. Non-linear spline regression was then used independently to identify critical time-points of change in the surgical repair rate to confirm the findings.

RESULTS

A total of 29 531 patients sustained an Achilles tendon rupture during the study period. Consistently, around 21 out of every 100 cases underwent surgical repair up to the first quarter of 2010. However, by the first quarter of 2014, only 6.5 cases per 100 had surgery. A statistically significant decrease in the rate of surgical repair was observed within one year of the presentation of landmark trial results in 2009 (p < 0.001). July 2009 was independently identified as a critical time at which the surgical repair rate began to significantly decline (p < 0.001). The dissemination of trial results was associated with a significant drop in the rate of surgical repair at non-teaching hospitals (p = 0.001).

CONCLUSION

The current study demonstrates that large, well-designed randomised trials, have the potential to encourage significant changes in the practice patterns of orthopaedic surgeons. Cite this article: Bone Joint J 2017;99-B:1629-36.

Surgical outcome of atypical subtrochanteric and femoral fracture related to bisphosphonates use in osteoporotic patients with or without teriparatide treatment

Background

Atypical subtrochanteric fracture and femoral fracture have been considered to be rare complications related to long-term bisphosphonates use. A reduced bone turnover rate may lead to delayed bone healing. Limited data have revealed that teriparatide treatment may reverse the effect of bisphosphonates and be effective in bone healing.

Methods

We reviewed patients with atypical subtrochanteric and femoral fracture related to bisphosphonates use between January 2008 and December 2014. Thirteen female patients were enrolled. Radiographic findings were compatible with the characteristics of atypical fracture. Surgical intervention was performed for all, and teriparatide use was advised postoperatively. Outcome measures included perioperative results, and clinical and radiographic outcome.

Results

Of the 13 female patients enrolled, 10 had subtrochanteric and 6 had proximal femoral fracture; 3 had bilateral fractures. The mean age of the patients at surgery was 70.15±6.36 years. Most fractures (68.8%) presented prodromal thigh pain. All patients were treated with an intramedullary fixation system without severe complications. The patients were divided into 2 groups based on whether they had received treatment with teriparatide or not. The mean time to bone union was 4.4 months in the teriparatide-treated group, and 6.2 months in the non-teriparatide-treated group (p=0.116). Six patients (75%) in the teriparatide-treated group and 4 (50%) in the non-teriparatide-treated group (p= 0.3) achieved bone union within 6 months. The means of the modified Harris Hip Score and Numerical Rating Scale were significantly better in the teriparatide-treated group at postoperative 6 months. Seven patients had the same ability to walk at the 1-year follow-up as they did before the atypical fracture.

Conclusions

Teriparatide treatment in patients with atypical fracture may help in fracture healing, hip function recovery, and pain relief in this reduced bone turnover patient group.

Location of atypical femoral fracture can be determined by tensile stress distribution influenced by femoral bowing and neck-shaft angle: a CT-based nonlinear finite element analysis model for the assessment of femoral shaft loading stress

INTRODUCTION

Loading stress due to individual variations in femoral morphology is thought to be strongly associated with the pathogenesis of atypical femoral fracture (AFF). In Japan, studies on AFF regarding pathogenesis in the mid-shaft are well-documented and a key factor in the injury is thought to be femoral shaft bowing deformity. Thus, we developed a CT-based finite element analysis (CT/FEA) model to assess distribution of loading stress in the femoral shaft.

PATIENTS AND METHODS

A multicenter prospective study was performed at 12 hospitals in Japan from August 2015 to February 2017. We assembled three study groups-the mid-shaft AFF group (n=12), the subtrochanteric AFF group (n=10), and the control group (n=11)-and analyzed femoral morphology and loading stress in the femoral shaft by nonlinear CT/FEA.

RESULTS

Femoral bowing in the mid-shaft AFF group was significantly greater (lateral bowing, p<0.0001; anterior bowing, p<0.01). Femoral neck-shaft angle in the subtrochanteric AFF group was significantly smaller (p<0.001). On CT/FEA, both the mid-shaft and subtrochanteric AFF group showed maximum tensile stress located adjacent to the fracture site. Quantitatively, there was a correlation between femoral bowing and the ratio of tensile stress, which was calculated between the mid-shaft and subtrochanteric region (lateral bowing, r=0.6373, p<0.0001; anterior bowing, r=-0.5825, p<0.001).

CONCLUSIONS

CT/FEA demonstrated that tensile stress by loading stress can cause AFF. The location of AFF injury could be determined by individual stress distribution influenced by femoral bowing and neck-shaft angle.

Treatment of Atypical Ulnar Fractures Associated with Long-Term Bisphosphonate Therapy for Osteoporosis: Autogenous Bone Graft with Internal Fixation

Long-term bisphosphonate use has been suggested to result in decreased bone remodelling and an increased risk of atypical fractures. Fractures of this nature commonly occur in the femur, and relatively few reports exist to show that they occur in other bones. Among eight previous reports of atypical ulnar fractures associated with bisphosphonate use, one report described nonunion in a patient who was treated with cast immobilization and another described ulna nonunion in one of three patients, all of whom were treated surgically with a locking plate. The remaining two surgical patients achieved bone union uneventfully following resection of the osteosclerotic lesion and iliac bone grafting before rigid fixation. We hypothesized that the discontinuation of bisphosphonate therapy, the use of teriparatide treatment, and low-intensity pulsed ultrasound (LIPUS) might have been associated with fracture healing.

Predisposing factors associated with atypical femur fracture among postmenopausal Korean women receiving bisphosphonate therapy: 8 years' experience in a single center

The risk factors for atypical femur fracture in patients exposed to bisphosphonates for at least 1 year were examined. Prolonged and continuous use of bisphosphonates, long-term use of glucocorticoids, and a higher body mass index were associated with increased risk of atypical femur fracture.

INTRODUCTION

The purpose of the present study is to determine whether rheumatoid arthritis (RA) and other clinical factors are associated with an increased risk of bisphosphonate (BP)-related atypical femur fracture (AFF).

METHODS

A retrospective nested case-control study of patients who had taken BPs for at least 1 year was conducted. Patients with AFF were identified by reviewing surgical and radiographic records. Three controls with no history of AFFs were randomly selected and age- and sex-matched to each patient with AFFs. Cox proportional hazard models were used to analyze the independent contribution of risk factors to BP-related AFF.

RESULTS

Among the 35,104 patients prescribed BPs for at least 1 year, 43 females (mean age, 68 years) suffered AFFs (0.12%). Patients with AFFs were exposed to BPs for a mean of 7.3 years. Patients with AFFs were exposed to BPs for longer than those without AFFs and continued treatment without a drug holiday. More patients with AFF than controls had taken glucocorticoids and disease-modifying anti-rheumatic drugs. Multivariate Cox regression analyses estimated that long-term use of glucocorticoids, prolonged exposure to BP without cessation, and every 1 kg/m² increase in the body mass index (BMI) increased the hazard ratio for AFFs by 3.0, 5.2, and 1.2, respectively.

CONCLUSIONS

Prolonged and continuous use of BPs, long-term use of glucocorticoids, and a higher BMI increase the risk of AFFs. Switching long-term BP and glucocorticoid users to other bone-protective agents should be considered.

Atypical femur fractures: a survey of current practices in orthopedic surgery

The results of a self-administered online survey demonstrate that orthopedic surgeons' management practices for AFF are variable. These data will inform the development of clinical practice guidelines.

INTRODUCTION

We aimed to determine current AFF treatment practices of orthopedic surgeons to inform clinical practice guideline development.

METHODS

A self-administered online survey was developed and sequentially posted on the Orthopaedic Trauma Association (OTA) website from July to August 2015 and the Canadian Orthopaedic Association (COA) website from December 2015 to January 2016. Level of confidence in diagnosis and treatment as well as treatment preferences between respondents who self-identified as trauma surgeons vs. non-trauma surgeons were compared.

RESULTS

A total of 172 completed surveys were obtained (OTA, N = 100, 58%; COA, N = 72, 8%). Seventy-eight percent of respondents had treated ≥1 AFF in the previous 6 months. Seventy-six percent reported feeling extremely or very confident in diagnosing AFF (trauma 84% vs. non-trauma surgeons 70%, p = 0.04), and 63% reported feeling extremely or very confident in treating AFF (trauma 82%, non-trauma surgeons 50%, p < 0.01). Preferred management for complete and symptomatic incomplete AFFs was surgical fixation with a cephalomedullary nail (CMN) by 88 and 79%, respectively, while close follow-up was preferred for asymptomatic incomplete AFFs in 72% of respondents. Trauma surgeons used the CMN more frequently than non-trauma surgeons (90 vs. 76% p = 0.03). In patients with bilateral AFFs, with one side surgically treated, 56% were extremely likely to surgically treat the contralateral side, if symptomatic. Most felt guidelines (81%) and educational resources (73%) would be valuable.

CONCLUSIONS

Current orthopedic treatment practices for AFFs are variable. The results of this survey will inform the development of practice guidelines and educational resources.

Atypical subtrochanteric fractures in Korean hip fracture study

In Korean, atypical subtrochanteric fractures (ASF) were rare. Higher BMI and use of bisphosphonate were significant risk factors of ASF.

INTRODUCTION

Recently, ASF have been reported to increase among patients on bisphosphonate. However, the incidence of ASF and the association between ASF and bisphosphonate use have not been well defined in Asian population. Our purposes are (1) to estimate the proportion of ASF among Korean patients with proximal femur fracture and (2) to determine the associated risk factors of ASF in the Korean patients.

METHODS

We conducted a multicenter (16 academic hospitals), prospective Korean hip fracture study on hip fracture in a cohort of patients aged 50 years or older from South Korea between July 2014 and May 2016. As a part of Korean hip fracture study, primary analysis examined the proportion of ASF among proximal femur fracture. To identify ASF, according to the definition by ASBMR task force, all radiographs of subtrochanteric fracture were reviewed. Associated risk factors for occurrence of ASF were also evaluated by using multivariable logistic regression analysis.

RESULTS

Among 1361 patients with proximal femoral fractures due to low-energy trauma, 17 fractures (1.2%) were identified as ASF. Higher BMI and use of bisphosphonate before injury were independent risk factors of ASF.

CONCLUSION

In Korean, ASF were rare. Higher BMI and use of bisphosphonate were significant risk factors of ASF.

Long-Term Oral Bisphosphonate Therapy and Fractures in Older Women: The Women's Health Initiative

OBJECTIVES

To examine the association between long-term bisphosphonate use and fracture in older women at high risk of fracture.

DESIGN

Retrospective cohort.

SETTING

Women's Health Initiative.

PARTICIPANTS

Older women who reported at least 2 years of bisphosphonate use in 2008-09 (N = 5,120).

MEASUREMENTS

Exposure data were from a current medications inventory. Outcomes (hip, clinical vertebral, wrist or forearm, any clinical fracture) were ascertained annually. Using multivariate Cox proportional hazards models, the association between duration of bisphosphonate use (3-5, 6-9, 10-13 years) and fracture was estimated, using 2 years as the referent group.

RESULTS

On average participants were 80 years old and were followed for 3.7 ± 1.2 years. There were 127 hip, 159 wrist or forearm, 235 clinical vertebral, and 1,313 clinical fractures. In multivariate-adjusted analysis, 10 to 13 years of bisphosphonate use was associated with higher risk of any clinical fracture than 2 years of use (hazard ratio (HR) = 1.29, 95% confidence interval (CI) = 1.07-1.57). This association persisted in analyses limited to women with a prior fracture (HR = 1.30, 95% CI = 1.01-1.67) and women with no history of cancer (HR = 1.36, 95% CI = 1.10-1.68). The association of 10 to 13 years of use, compared with 2 years of use, was not statistically significant for hip (HR = 1.66, 95% CI = 0.81-3.40), clinical vertebral (HR = 1.65, 95% CI = 0.99-2.76), or wrist fracture (HR = 1.16, 95% CI = 0.67-2.00).

CONCLUSION

In older women at high risk of fracture, 10 to 13 years of bisphosphonate use was associated with higher risk of any clinical fracture than 2 years of use. These results add to concerns about the benefit of very long-term bisphosphonate use.

New insights into human farnesyl pyrophosphate synthase inhibition by second-generation bisphosphonate drugs

Pamidronate, alendronate, APHBP and neridronate are a group of drugs, known as second-generation bisphosphonates (2G-BPs), commonly used in the treatment of bone-resorption disorders, and recently their use has been related to some collateral side effects. The therapeutic activity of 2G-BPs is related to the inhibition of the human Farnesyl Pyrophosphate Synthase (hFPPS). Available inhibitory activity values show that 2G-BPs act time-dependently, showing big differences in their initial inhibitory activities but similar final IC₅₀ values. However, there is a lack of information explaining this similar final inhibitory potency. Although different residues have been identified in the stabilization of the R₂ side chain of 2G-BPs into the active site, similar free binding energies were obtained that highlighted a similar stability of the ternary complexes, which in turns justified the similar IC₅₀ values reported. Free binding energy calculations also demonstrated that the union of 2G-BPs to the active site were 38 to 54 kcal mol^-1 energetically more favourable than the union of the natural substrate, which is the basis of the inhibition potency of the hFPPS activity.

Lateral Femoral Bowing and the Location of Atypical Femoral Fractures

Purpose

Atypical femoral fractures (AFFs) occur in two distinct part, subtrochanter and diaphysis. The aim of this study was to investigate the relationship between the lateral femoral bowing angle and the location of AFF.

Materials and Methods

This study included a total of 56 cases in 45 patients who underwent surgical treatment between January 2010 and December 2015. For the diaphyseal and subtrochanteric AFFs, we evaluated the relationship between the anatomic location and lateral femoral bowing angle. Lateral femoral bowing angle was measured by two orthopaedic surgeons and average value of two calibrators was used in statistic analysis. Other variables like age, height, weight, body mass index and bone mineral density were also evaluated. We also calculated the cutoff value for the location of the fractures from the raw data.

Results

The average lateral femoral bowing angle was 10.10°±3.79° (3°-19°) in diaphyseal group and 3.33°±2.45° (1.5°-11°) in subtrochanter group. Lateral femoral bowing angle was statistically significant in logistic regression analysis. According to the receiver operating characteristic curve, cutoff value for the location of the fracture was 5.25°. In other words, the femoral diaphyseal fractures are more frequent if the lateral femoral bowing angle is greater than 5.25°.

Conclusion

The lateral femoral bowing angle is associated with the location of the AFFs and the cutoff value of lateral femoral bowing angle was 5.25°.

Atypical Fracture of the Sternum After Long-Term Alendronate Plus Cholecalciferol Treatment: A Case Report

A 55-year-old woman developed an atraumatic sternum fracture during treatment with alendronate for osteoporosis. The woman received alendronate 70 mg in combination with cholecalciferol 5600 IU once weekly, as well as nonsteroidal anti-inflammatory drugs. After 4 years of treatment, following a dorsal flexion with no direct thoracic trauma, the patient suffered a fracture of the sternum, with an X-ray revealing sternal body fracture. This fracture was seen to be transverse, noncomminuted and without displacement. Magnetic resonance imaging was carried out to rule out the presence of either a pathological fracture or a fracture resulting from osteoporotic fragility, and showed a triple sternal fracture involving the body, as well as the upper and lower manubrium of the sternum. This fracture presented the features of an atypical femur fracture, except for the location. The alendronate and cholecalciferol combination was discontinued and denosumab was prescribed. After the withdrawal of alendronate, the patient showed clinical improvement, with a decrease in pain, and is currently having routine checkups. The causality algorithm of the Spanish Pharmacovigilance System shows a score of 5, indicating a possible relationship between the patient’s sternum fracture and her use of the suspect drug (Naranjo scale 6 = probable).

Addressing the Crisis in the Treatment of Osteoporosis: A Path Forward

Considerable data and media attention have highlighted a potential "crisis" in the treatment of osteoporosis. Specifically, despite the availability of several effective drugs to prevent fractures, many patients who need pharmacological therapy are either not being prescribed these medications or if prescribed a medication, are simply not taking it. Although there are many reasons for this "gap" in the treatment of osteoporosis, a major factor is physician and patient concerns over the risk of side effects, especially atypical femur fractures (AFFs) related to bisphosphonate (and perhaps other antiresorptive) drug therapy. In this perspective, we review the current state of undertreatment of patients at increased fracture risk and suggest possible short-, intermediate-, and long-term approaches to address patient concerns, specifically those related to AFF risk. We suggest improved patient and physician education on prodromal symptoms, extended femur scans using dual-energy X-ray absorptiometry (DXA) to monitor patients on antiresorptive treatment, better identification of high-risk patients perhaps using geometrical parameters from DXA and other risk factors, and more research on pharmacogenomics to identify risk markers. Although not the only impediment to appropriate treatment of osteoporosis, concern over AFFs remains a major issue and one that needs to be resolved for effective dissemination of existing treatments to reduce fracture risk. © 2017 American Society for Bone and Mineral Research.

Healing of Atypical Subtrochanteric Femur Fractures After Cephalomedullary Nailing: Which Factors Predict Union?

OBJECTIVES

The purpose of this study was to determine the healing rate and time to union of atypical subtrochanteric fractures treated with cephalomedullary nailing.

DESIGN

Retrospective review, descriptive, and analytic study.

SETTING

Six level 1 trauma centers.

PATIENTS/PARTICIPANTS

The study included 42 patients with 48 displaced, atypical, bisphosphonate-associated subtrochanteric femur fractures who underwent surgical intervention.

INTERVENTION

Cephalomedullary femur nailing.

MAIN OUTCOME MEASUREMENT

The main outcome measures were radiologic healing and time to union.

RESULTS

The primary healing rate after cephalomedullary nailing of bisphosphonate-associated subtrochanteric femur fractures was 68.7% (33/48 patients). Mean time to union was 10.7 months. Malalignment was determined using the differences in neck-shaft angle (the difference between the normal side and the surgically repaired side) and sagittal angulation. These all proved to be significantly correlated with failure and delayed healing time. The cutoff points for neck-shaft angle, difference in neck-shaft angle, and sagittal angulation were 125.6, 4.4, and 5.5 degrees, respectively (receiver operating characteristic curve analysis).

CONCLUSIONS

The healing rate of atypical subtrochanteric femur fractures treated with cephalomedullary nailing is lower than that previously reported for atypical femur fractures. The quality of fracture reduction proved to be the most important factor in bony union and time to union.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Bone Structure and Turnover Status in Postmenopausal Women with Atypical Femur Fracture After Prolonged Bisphosphonate Therapy

Atypical femur fracture (AFF), a serious complication of long-term bisphosphonate therapy, is usually preceded by an incomplete fracture appearing on the lateral femur. AFF is most likely the result of severely suppressed bone turnover (SSBT). However, the differences in bone structure and turnover between patients with incomplete and complete AFF remain unknown. We examined trans-iliac bone biopsies from 12 white postmenopausal women with AFF (incomplete = 5; complete = 7) on BP therapy of >5 years and 43 healthy white premenopausal women. Histomorphometric measurements were performed separately in cancellous, intracortical and endosteal envelopes. Of the 43 histomorphometric measurements on 3 difference bone surfaces (cancellous, intracortical and endosteal), only 2 bone resorption variables (Oc.S/BS and Oc.S/NOS) on the endosteal surface were significantly lower in patients with complete AFF than those with incomplete AFF. Compared to healthy premenopausal women, the trabecular bone volume, thickness and number were all significantly lower in patients with AFF. The dynamic bone formation variables in patients with AFF were significantly reduced on all bone surfaces. The likelihood of a biopsy with no tetracycline labeling was significantly higher in AFF patients than in healthy premenopausal women. Based on these results, we conclude that there are no significant differences in bone turnover between patients with incomplete and complete AFF, suggesting that the suppression of bone turnover had already existed in the femur with incomplete AFF. Compared to healthy premenopausal women, bone turnover is similarly suppressed in patients with either type of AFF.

The effect of patient, provider and surgical factors on survivorship of high tibial osteotomy to total knee arthroplasty: a population-based study

PURPOSE

The aim of this study was to identify the survivorship of high tibial osteotomy (HTO) to total knee arthroplasty (TKA) on a population level, and identify the patient, provider and surgical factors that influenced eventual TKA.

METHODS

Administrative records from physician billings and hospital admissions were used to identify all adults in Ontario, Canada, who underwent an HTO from 1994 to 2010. The primary outcome was time to TKA, which was estimated using Kaplan-Meier (KM) survival analysis. A Cox proportional hazards model examined the risk associated with patient factors (age, sex, income and co-morbidity score), provider factors (hospital status, surgeon volume and surgeon year in practice) and surgical factors (concurrent ligament reconstruction or bone grafting; and previous chondral or meniscal surgery).

RESULTS

A total of 2671 patients who underwent HTO met inclusion. The median age was 46 years (interquartile range 39-53 years), and 62 % were male. The KM survivorship of HTO to TKA at 10 years was 0.67 ± 0.01. Older age [HR 1.05 (95 % CI 1.04, 1.06), p < 0.001; 5 % increased risk for each year over age 46], female sex [HR 1.35 (95 % CI 1.17, 1.55), p < 0.001], higher comorbidity score [HR 1.58 (95 % CI 1.12, 2.22), p = 0.009] and a prior history of arthroscopy/meniscectomy [HR 1.24 (95 % CI 1.08, 1.43), p = 0.002] increased the risk of eventual TKA. However, HTO with concurrent ligament reconstruction was associated with lower [HR 0.62 (95 % CI 0.43, 0.88), p = 0.008] risk of eventual TKA.

CONCLUSION

In this population, two-thirds of patients were able to avoid a TKA for 10 years after HTO. Specific factors such as older age, female sex, higher comorbidity and prior meniscectomy lowered survival rates. An understanding of patient risk factors for conversion to TKA may help guide surgeons in their selection of patients who will benefit most from HTO.

LEVEL OF EVIDENCE

Retrospective cohort study, III.

Drug-Related Adverse Events of Osteoporosis Therapy

Postmenopausal osteoporosis is associated with microarchitectural deterioration and increased risk of fracture. Osteoporosis therapy effectively reduces the risk of vertebral, nonvertebral, and hip fracture and has been associated with increased survival. Currently approved treatments for osteoporosis include bisphosphonates, denosumab, selective estrogen receptor modulators, and teriparatide. This article reviews the adverse events of therapy associated with these medical interventions. Hormone replacement therapy is not included, because it is no longer indicated for the treatment of osteoporosis in all countries. Calcitonin and strontium ranelate are also not included, because their indication for osteoporosis has recently been limited or withdrawn.

The epidemiology and trends in management of acute Achilles tendon ruptures in Ontario, Canada: a population-based study of 27 607 patients

AIMS

The aims of this study were to establish the incidence of acute Achilles tendon rupture (AATR) in a North American population, to select demographic subgroups and to examine trends in the management of this injury in the province of Ontario, Canada.

PATIENTS AND METHODS

Patients ≥ 18 years of age who presented with an AATR to an emergency department in Ontario, Canada between 1 January 2003 and 31 December 2013 were identified using administrative databases. The overall and annual incidence density rate (IDR) of AATR were calculated for all demographic subgroups. The annual rate of surgical repair was also calculated and compared between demographic subgroups.

RESULTS

A total of 27 607 patients (median age, 44 years; interquartile range 26 to 62; 66.5% male) sustained an AATR. The annual IDR increased from 18.0 to 29.3 per 100 000 person-years between 2003 and 2013. The mean IDR was highest among men between the ages of 40 and 49 years (46.0/100 000 person-years). The annual rate of surgical repair dropped from 20.1 in 2003 to 9.2 per 100 AATRs in 2013. There was a noticeable decline after 2009.

CONCLUSION

The incidence of AATR is increasing in Ontario, while the annual rate of surgical repair is decreasing. A sharp decline in the rate of surgical repair was noted after 2009. This coincided with the publication of several high-quality RCTs which showed similar outcomes for the 'functional' non-operative management and surgical repair. Cite this article: Bone Joint J 2017;99-B:78-86.

Scoring System for Identifying Impending Complete Fractures in Incomplete Atypical Femoral Fractures

CONTEXT

Although impending incomplete atypical femoral fractures (AFFs) require prophylactic fixation, there is still a lack of study on predicting complete fracture among the incomplete AFFs.

OBJECTIVE

Our purposes are to develop a scoring system to predict progression into complete fracture and to evaluate its reliability and validity.

DESIGN, SETTING, AND PATIENTS

We reviewed 46 incomplete AFFs in 44 patients who did not undergo prophylactic fixation. A weighted scoring system, including four identified risk factors (the site, severity of pain, status of the contralateral femur, and the extent of radiolucent line), was developed. We evaluated its interobserver reliability by using intraclass correlation coefficiency (ICC) and its accuracy using receiver operator characteristic (ROC) curve. The validity of the scoring system was tested in a different cohort.

INTERVENTION

Observational study.

MAIN OUTCOME MEASURE

Progression to complete fracture within 6 months.

RESULTS

Among 46 incomplete fractures, 13 developed a complete fracture within 6 months. The probability of complete fracture increased abruptly when the score was 8 points or more. The proposed scoring system showed an almost perfect reliability (ICC, 0.997; 95% confidence interval, 0.995 to 0.998) and higher accuracy than any single risk factor in ROC curve. In the different series, the positive predictive value was 100% and the sensitivity was 75%, when cutoff value was 8 points.

CONCLUSION

The progression to complete fracture could be predicted by using our scoring system. Incomplete AFF with scores <8 points can be treated conservatively, whereas lesions with scores ≥8 require prophylactic fixation.

Bilateral atypical femur fractures without bisphosphonate exposure

Atypical femur fractures have common radiographic features that set them apart from more typical higher-energy subtrochanteric femur fractures. They are noncomminuted, transverse fractures with medial spiking of the femoral cortex and increased lateral cortical thickness. These fractures have been associated in the literature with the use of bisphosphonate medications. This case describes bilateral atypical femur fractures in a patient with a medical history devoid of bisphosphonate use. We present his history, co-morbidities, and subsequent treatment. From this case, we call attention to bisphosphonate use as not the only cause of subtrochanteric femur fractures with atypical features and highlight that some patients may sustain these injuries even bilaterally without use of the medications. In addition, it is important to identify this fracture type and obtain imaging of the contralateral femur to facilitate prophylactic treatment if needed.

Sensitivity and specificity of radiographic characteristics in atypical femoral fractures

Using the American Society for Bone and Mineral Research Task Force case definition for atypical femoral fractures, sensitivity and specificity of radiographic fracture characteristics were calculated. Fracture pattern was the most sensitive and specific characteristic. This suggests that some characteristics should be weighted more heavily when identifying these fractures.

INTRODUCTION

To estimate the sensitivity and specificity of each radiographic criterion in the 2013 ASBMR atypical femoral fracture (AFF) case definition for distinguishing AFF from other subtrochanteric/diaphyseal fractures (non-AFF) among women enrolled in a large integrated health care organization.

METHODS

Radiographs from 55 physician-confirmed AFFs and a sample of 39 non-AFFs were reviewed by four independent expert reviewers representing four medical specialties. One image per fracture was selected for review. Using a standardized data collection tool, based on the 2013 AFF case definition, reviewers indicated the presence or absence of the following characteristics viewable on radiograph: fracture pattern, comminution, periosteal and/or endosteal thickening, and cortical thickening. Sensitivity and specificity for each characteristic was calculated for each reviewer and summarized across reviewers with the mean and range. Agreement across reviewers was quantified using Fleiss's kappa (FK) statistic.

RESULTS

The most sensitive factors distinguishing AFF from non-AFF were lateral cortex transverse fracture pattern (mean 93.6 %, range 85.5-98.2 %), medial cortex transverse or oblique fracture pattern (mean 84.1 %, range 72.7-98.2 %), and minimal/non-comminution (mean 93.2 %, range 89.1-98.2 %). Specificity was the greatest for lateral cortex transverse fracture pattern (mean 95.5 %, range 92.3-97.4 %). Agreement across reviewers was the highest for lateral cortex transverse fracture pattern (FK 0.83) and incomplete fracture through the lateral cortex only (FK 0.80).

CONCLUSION

Lateral cortex transverse fracture pattern was the most sensitive and specific characteristic and the most highly agreed upon across reviewers. Other characteristics were less readily agreed upon across reviewers. Measurement of discrete combinations of individual characteristics may enhance sensitivity and/or specificity.

Long-Term Proton Pump Inhibitor Use Is Not Associated With Changes in Bone Strength and Structure

OBJECTIVES

Multiple studies have reported an association between proton pump inhibitor (PPI) use and fracture. However, the causality of this association is questionable, as there is not a well defined mechanism of action, nor is there evidence of an effect on PPIs on areal bone mineral density (aBMD) using dual photon X-ray absorptiometry (DXA). It is possible that PPIs may induce changes in bone structure which would predispose to fracture in the absence of changes in aBMD. We used three-dimensional quantitative computed tomography (3D-QCT) imaging to determine if long-term PPI use was associated with structural changes in bone independent of aBMD.

METHODS

We enrolled a sample of long-term (≥5 years) PPI users matched to a similar cohort of persons with no PPI use in the previous 5 years. All subjects underwent assessment of aBMD using DXA, volumetric BMD using 3D-QCT, as well as markers of bone metabolism. Measures of bone strength, including buckling ratio and section modulus, were also compared between the two samples.

RESULTS

104 subjects were enrolled (52 PPI users and 52 PPI non-users). There were no differences detected in standard BMD, volumetric BMD, markers of bone metabolism or measures of bone strength between the two groups.

CONCLUSIONS

Long-term PPI use is not associated with any changes in bone mineral density or bone strength that would predispose to an increased risk of fracture. These findings provide further evidence that the association between PPI use and fracture is not causal.

Anterolateral femoral bowing and loss of thigh muscle are associated with occurrence of atypical femoral fracture: Effect of failed tension band mechanism in mid-thigh

BACKGROUND

The purpose of this study was to characterize anterolateral bowing of the femur using X-rays and muscular atrophy in the mid-thigh using computed tomography (CT) in patients with atypical femoral fractures (AFFs). We then compared the results with those of an intertrochanteric fracture to understand whether these measures act as causative factors of AFFs.

METHODS

From January 2009 to December 2015, 37 patients with complete AFF and 12 patients with incomplete AFF were enrolled in this study. Lateral femoral bowing, anterior femoral bowing, cross-sectional area (CSA), and attenuation coefficient of thigh muscles in the AFF group are measured and compare with those in the intertrochanteric fracture group.

RESULTS

Lateral and anterior femoral bowing in the AFF group were significantly higher than those in the intertrochanteric fracture group. The level of fracture was found to be significantly associated with lateral and anterior femoral bowing (r = 0.569, r² = 0.324, p < 0.001; r = -0.530, r² = 0.281, p < 0.001, respectively). Total CSA and CSA of anterior and medial compartments were significantly lower in the AFF group (p < 0.05). The attenuation coefficient of the total thigh muscle and all three compartments in the AFF group were significantly lower than those in the intertrochanteric fracture group (p < 0.05).

CONCLUSIONS

This study demonstrated that anterolateral femoral bowing and loss of thigh muscle were highly associated with the occurrence of AFFs.

Atypical femoral fracture after receiving antiresorptive drugs in breast cancer patients with bone metastasis

Background

Atypical femoral fracture (AFF) occurs with minor trauma in patients receiving antiresorptive drugs such as bisphosphonate and denosumab. We hypothesized that patients with bone metastasis who receive higher doses of antiresorptive drugs tend to experience AFF more frequently. This study aimed to investigate the prevalence rate of AFF in patients receiving antiresorptive drugs for bone metastasis of breast cancer.

Methods

Based on the database from our hospital, patients with breast cancer between March and September 2014 were investigated. Thirty-two patients with bone metastasis who received higher doses of antiresorptive drugs were included for analysis and defined as the metastasis (M) group. For the control (C) group, 32 patients in the same period with breast cancer without bone metastasis who did not undergo antiresorptive drug therapy were included. We evaluated the localized periosteal thickening of the lateral cortex (beaking) and femoral neck-shaft angle in CT scout view, the periods from induction of antiresorptive drugs to the appearance of beaking, and the occurrence rate of complete fracture. The 2 groups were compared.

Results

Of the 64 limbs in 32 patients of the M group, 8 limbs in 6 patients showed beaking at the subtrochanteric area (12.5%). After the occurrence of beaking, 5 limbs in 3 patients eventually had a complete fracture with minor trauma (7.8%). On the other hand, no beaking was observed in the C group.

Conclusions

The frequency of AFF in patients with breast cancer receiving bisphosphonate and/or denosumab for bone metastasis was high. More attention should be paid to the occurrence of AFF in these patients than osteoporotic patients.

[Atypical subtrochanteric femur fracture under alendronate therapy in spite of an intramedullar implant]

There are a number of case reports about women undergoing long-term bisphosphonate therapy who have suffered an atypical subtrochanteric or femoral shaft fracture due to an inadequate trauma.The present case reports on a patient who underwent a subtrochanteric femur fracture with the inserted AO femur interlocking nail.